Trace concentrations of graphene oxide and magnetic graphene oxide rescue anaerobic municipal sludge digesters under stress
This study evaluated long-term performance of graphene oxide (GO) and magnetic GO (MGO) nanosheets in semi-continuous-flow anaerobic digestion (AD) of municipal sludge over 230 days. At organic loading rates (OLRs) of 2.6 and 3.4 g chemical oxygen demand (COD)<sub>fed</sub>/L/day, 20 and 200 mg/L of GO and MGO did not affect AD performance. However, at an OLR of 5.2 g COD<sub>fed</sub>/L/day, where control digesters failed, 20 and 200 mg/L of GO and MGO sustained biogas yields at 190 mL/g COD<sub>fed</sub>/day, similar to yields at lower OLRs (2.6 and 3.4 g COD<sub>fed</sub>/L/day). This performance persisted after thedaily nanosheet replenishment stopped. Improvements were due to enhanced conductivity and microbial syntropy. The results showed a strong correlation with previous biochemical methane potential (BMP) assays, positioning BMP as a predictive tool for continuous-flow AD performance. Overall, this study demonstrated potential of GO/MGO nanosheets to improve the stability and efficiency of AD systems under stress.
Authors
- Milad Goodarzi (ORCID: https://orcid.org/0000-0002-2860-2041)
- Mohammad Arjmand (ORCID: https://orcid.org/0000-0002-8812-5638)
- Çiğdem Eskicioğlu (ORCID: https://orcid.org/0000-0002-7673-134X)
Institutions
- Vancouver Island University (CA)
- University of British Columbia, Okanagan Campus (CA)
- Okanagan University College (CA)
Publication Details
- Journal
- Bioresource Technology
- Published
- 2024-12-03
- DOI
- https://doi.org/10.1016/j.biortech.2024.131936
- Citations
- 4
- Primary Topic
- Membrane Separation Technologies
- Type
- article
- Field-Weighted Citation Impact
- 0.81
Funders
- Natural Sciences and Engineering Research Council of Canada